software/bios: temporarily disable netboot and flashboot to save memory
top.py, lm32_config.v, linker.ld: use static hardcoded rom for bios
add spiflash core
lx9crg: add crg for lx9 microboard
make.py, top.py: tweaks for lx9 microboard
tdcdtc: preliminary version of serdes based TDC+DTC wishbone peripheral